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<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>

<body>
    <div></div>
    <script>
        console.log(location.search); // ?uname=andy
        // 1.先去掉？  substr('起始的位置'，截取几个字符);
        var params = location.search.substr(1); // uname=andy，1默认起始位置1，截取字符为全部
        console.log(params);

        //2.利用等号=把字符串分割为数组split
        var arr = params.split('=');
        console.log(arr);

        var div = document.querySelector('div');

        //3.把数据写入div中利用innerHTML
        div.innerHTML = arr[1] + '欢迎你';


    </script>
</body>

</html>